Abstract

SANCHEZ, Otto; DE MARADE, Sonia  and  GUERRA, Dania. Trisomía 21. Reporte de dos Casos con Cariotipos poco usuales. Invest. clín [online]. 2001, vol.42, n.1, pp.43-50. ISSN 0535-5133.

We report two patients with trisomy 21 whose cariotypes revealed unusual translocations. In the first case there was a tandem translocation with two chromosomes 21 attached to the long arm of chromosome 10 (45,XX + tan(10:21;21). In the second case there was an inverted tandem translocation between two chromosomes 21 attached through their long arms (46,XY+ dic(21q:21q). The clinical picture in both patients was not different from the usually found in trisomy 21. Since the parent’s cariotypes were normal in both cases, it is assumed that both translocations arose "de novo". The need for cariotyping all cases of Down syndrome is emphasized.

Keywords : Trisomy 21; Down Syndrome; translocation; tandem translocation..